U.S. Pat. No. 5,078,589 (Inventor: OSUNA-DIAZ; Publication Date: Jan. 7, 1992) discloses an arrangement for independently controlling shutoff and flow to a cavity gate in a multi-cavity injection mold apparatus. A plurality of valve pins are mounted to a movable holder plate. Each of the valve pins is aligned with a cavity gate and is movable thereinto to control shutoff. A plurality of fixed-position plunger sleeves are: (i) each mounted over a respective valve pin, and (ii) adjustably positioned with respect to a restriction feature in a supply passage upstream of the associated gate.
U.S. Pat. No. 6,056,535 (Inventor: SHIMIZU; Publication Date: May 2, 2000) discloses an injection molding machine including a processing pin provided in a fixed mold side. A movable member is arranged in a space between a fixed mold and a fixed plate. The processing pin can be moved forward and backward together with the movable member with a rear-end portion thereof fixed to the movable member. An end portion of the processing pin is inserted into a mold plate so that it can go in and out of a gate or a cavity by a forward movement and a backward movement of the movable member, which is moved by a drive unit. The above construction may eliminate positional limitation due to a position of a projecting pin in a conventional injection molding machine.
U.S. Pat. No. 6,276,916 (Inventor: SCHAD et al.; Publication Date: Aug. 21, 2001) discloses a failsafe device or a pressure relief mechanism, for a shooting pot actuator in an injection molding machine. The shooting pot actuator has multiple pusher rods mounted on a plate. The plate holds the multiple pusher rods. Moving the plate depresses injection pistons of the shooting pot and injects molten material into a number of mold cavities. To avoid damage to the machine from the pusher rods for the case where an injection piston seizes, the failsafe device is used to mount the pusher rods to the plates. A shearing member is interposed, or sandwiched, between a first aperture and a second aperture. Typically, the shearing member is a plate that, in normal operating conditions, blocks rearward movement of the pusher rods. However, when a predetermined shear force is applied to the plate, the shearing member becomes sheared and the pusher rod retracts within the channel thereby alleviating the pressure. The failsafe device can be paired with a seizure detection system that: (i) uses a laser beam that detects seizure of the piston and the valve gate, and (ii) provides appropriate notification or control signals.
U.S. Pat. No. 6,755,641 (Inventor: NAKANISHI; Publication Date: Jun. 29, 2004) discloses a stack injection molding apparatus that has: (i) a first arrays of valve gate injection nozzles, (ii) a second array of valve gate injection nozzles, and (iii) separate mechanisms for independently actuating the nozzles of each array. A separate reciprocating yoke plate engages the valve pins of each nozzle array. The yoke plate is actuated by either one centrally located actuator or a pair of symmetrically located actuators.
U.S. Pat. No. 7,131,834 (Inventor: BABIN et al.; Publication Date: Nov. 11, 2006) discloses an adjustment device for a valve pin on an injection molding machine, and particularly on a multi-cavity machine having a plurality of valve pins mounted on a common yoke plate, which is actuated by a common actuator. The adjustment device includes: (i) a pin holder for holding the valve pin, and (ii) a locking member. The pin holder has two threaded portions. The first threaded portion is adjustable within a threaded receiving hole in the yoke plate. The second threaded portion is received by the locking member. The locking member has a bottom shoulder which butts against the yoke plate, and retains the pin holder in place.